Common ways to produce electrical power from a rotor based apparatus are using turbines and alternators. Typical turbine system comprises of rotor blades that traps the wind flow or the water flow energy to do rotational motions, in order to generate electrical power.
Due to their spanning size they are not practical for moving vehicle. Most turbines rotor blades needs huge space to rotate, as disclosed, for example in, U.S. Pat. Nos. 4,447,738 (1984), 6,541,877 (2003), 6,400,039 (2002), 4,340,822 (1982), 2,054,383 (1936), 5,798,632 (1998), 4,299,198 (1981), 554,138 (1896), 5,213,470 (1993), 847,140 (1907), 6,465,901 (2002), and 6,285,090 (2001).
Thus these turbines need large space for stationary installations and it is not practical for use with any moving object in motion. Generally, those turbines that produce a high volume of electric current require huge structural space. These cost a significant amount of money and are more complex to operate and install.
Often, due to turbine's huge structure, wind or lightning contributes to its failure and knocks-out the whole turbine on the ground. This can be very serious safety issue.
Many turbine designs inner center-coils and outer coils (stators). In most scenarios the inner center-coil rotates and the outer-coil stays stationary.
To rotate inner center-coil it needs shaft with a rotor, with or without rotor blades. Rotor blades themselves occupy a huge space of the structure, and the shaft occupies huge length to rotate center-coil.
A common way to generate electrical power at large scale in this century is through wind turbines.
Power generation for smaller application like air/water surface and air based vehicles uses alternators. An alternator has a rotor, driven by belts to generate electrical power to provide power vehicle and charge battery. The rotor has to be driven by engine or other apparatus. Hence an alternator is not practical for capturing wind or water flow energy. See, for example, U.S. Pat. Nos. 6,897,575 (2005), 7,566,980 (2009), 5,998,903 (1999), 6,740,995 ((2004), 6,455,946 (2002), 7,629,719 (2009), 20060208581 (2007).